= Solution
The star is near the southwestern end of the main <fault slip> patch, so a much longer part of the <finite-source rupture> propagates northeastward. For comparable distances, ground conditions and buildings, \b[the northeastern site receives the stronger, shorter direct pulse; the southwestern site receives the weaker, longer direct shaking]. This is <rupture directivity>.<What is Directivity by United States Geological Survey>[Explanation of focusing by successive rupture elements]{ref}
For a segment of length $\ell$, <rupture velocity> $v_r$ and <seismic wave> speed $c>v_r$, successive arrival times span approximately
$$
\Delta t_{\rm forward}=\ell(1/v_r-1/c),\qquad \Delta t_{\rm backward}=\ell(1/v_r+1/c).
$$
Forward arrivals overlap and concentrate <energy> into a shorter pulse. Backward arrivals spread out. The supplied <finite-source rupture> is not perfectly unilateral, so the prediction concerns the dominant contribution. <Seismic radiation patterns>, <seismic attenuation>, sediment amplification and building response can alter the ranking of actual damage or total coda duration.
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